How do I serialize an associated object differently using Jackson and annotations?

Question

Given the following class hierarchy, I would like Foo to be serialized differently depending on the context it is used in my class hierarchy.

public class Foo {
         


        

Answer 1

I would use the google code gson
documentation in here https://code.google.com/p/google-gson/
Maven dependency is:

            com.google.code.gson
            gson
            2.2.1
        

The annotations are like this:
To expose the field user the @Expose annotation
To generate a special name for the field in the parsed json user the @SerializedName("fieldNameInJSON") annotation
So your classes would look like this:

    public class Foo {
@SerializedName("bar")
    @Expose
        public String bar;
@SerializedName("biz")
    @Expose
        public String biz;
    }

    public class FooContainer {
@SerializedName("fooA")
    @Expose
        public Foo fooA;
@SerializedName("fooB")
    @Expose
        public Foo fooB;
    }

To serialize to JSON you will use a code that looks like this:

public String convertToJSON(FooContainer fc) {
        if (fc != null) {
            GsonBuilder gson = new GsonBuilder();
            return gson.excludeFieldsWithoutExposeAnnotation().create().toJson(fc);
        }
        return "";
    }

It would look the same for Lists for example:

public String convertToJSON(List fcs) {
            if (fcs != null) {
                GsonBuilder gson = new GsonBuilder();
                return gson.excludeFieldsWithoutExposeAnnotation().create().toJson(fcs);
            }
            return "";
        }